Support for multi table expressions in generic OrderBy/ThenBy/Desc APIs

Author: mythz

src/ServiceStack.OrmLite/Expressions/SqlExpression.cs

@@ -803,10 +803,11 @@ public virtual SqlExpression<T> OrderBy(Expression<Func<T, object>> keySelector)
             return OrderByInternal(keySelector);
         }
 
-        public virtual SqlExpression<T> OrderBy<Table>(Expression<Func<Table, object>> keySelector)
-        {
-            return OrderByInternal(keySelector);
-        }
+        public virtual SqlExpression<T> OrderBy<Table>(Expression<Func<Table, object>> fields) => OrderByInternal(fields);
+        public virtual SqlExpression<T> OrderBy<Table1, Table2>(Expression<Func<Table1, Table2, object>> fields) => OrderByInternal(fields);
+        public virtual SqlExpression<T> OrderBy<Table1, Table2, Table3>(Expression<Func<Table1, Table2, Table3, object>> fields) => OrderByInternal(fields);
+        public virtual SqlExpression<T> OrderBy<Table1, Table2, Table3, Table4>(Expression<Func<Table1, Table2, Table3, Table4, object>> fields) => OrderByInternal(fields);
+        public virtual SqlExpression<T> OrderBy<Table1, Table2, Table3, Table4, Table5>(Expression<Func<Table1, Table2, Table3, Table4, Table5, object>> fields) => OrderByInternal(fields);
 
         private SqlExpression<T> OrderByInternal(Expression keySelector)
         {
@@ -843,10 +844,11 @@ public virtual SqlExpression<T> ThenBy(Expression<Func<T, object>> keySelector)
             return ThenByInternal(keySelector);
         }
 
-        public virtual SqlExpression<T> ThenBy<Table>(Expression<Func<Table, object>> keySelector)
-        {
-            return ThenByInternal(keySelector);
-        }
+        public virtual SqlExpression<T> ThenBy<Table>(Expression<Func<Table, object>> fields) => ThenByInternal(fields);
+        public virtual SqlExpression<T> ThenBy<Table1, Table2>(Expression<Func<Table1, Table2, object>> fields) => ThenByInternal(fields);
+        public virtual SqlExpression<T> ThenBy<Table1, Table2, Table3>(Expression<Func<Table1, Table2, Table3, object>> fields) => ThenByInternal(fields);
+        public virtual SqlExpression<T> ThenBy<Table1, Table2, Table3, Table4>(Expression<Func<Table1, Table2, Table3, Table4, object>> fields) => ThenByInternal(fields);
+        public virtual SqlExpression<T> ThenBy<Table1, Table2, Table3, Table4, Table5>(Expression<Func<Table1, Table2, Table3, Table4, Table5, object>> fields) => ThenByInternal(fields);
 
         private SqlExpression<T> ThenByInternal(Expression keySelector)
         {
@@ -867,10 +869,11 @@ public virtual SqlExpression<T> OrderByDescending(Expression<Func<T, object>> ke
             return OrderByDescendingInternal(keySelector);
         }
 
-        public virtual SqlExpression<T> OrderByDescending<Table>(Expression<Func<Table, object>> keySelector)
-        {
-            return OrderByDescendingInternal(keySelector);
-        }
+        public virtual SqlExpression<T> OrderByDescending<Table>(Expression<Func<Table, object>> keySelector) => OrderByDescendingInternal(keySelector);
+        public virtual SqlExpression<T> OrderByDescending<Table1, Table2>(Expression<Func<Table1, Table2, object>> fields) => OrderByDescendingInternal(fields);
+        public virtual SqlExpression<T> OrderByDescending<Table1, Table2, Table3>(Expression<Func<Table1, Table2, Table3, object>> fields) => OrderByDescendingInternal(fields);
+        public virtual SqlExpression<T> OrderByDescending<Table1, Table2, Table3, Table4>(Expression<Func<Table1, Table2, Table3, Table4, object>> fields) => OrderByDescendingInternal(fields);
+        public virtual SqlExpression<T> OrderByDescending<Table1, Table2, Table3, Table4, Table5>(Expression<Func<Table1, Table2, Table3, Table4, Table5, object>> fields) => OrderByDescendingInternal(fields);
 
         private SqlExpression<T> OrderByDescendingInternal(Expression keySelector)
         {
@@ -919,10 +922,11 @@ public virtual SqlExpression<T> ThenByDescending(Expression<Func<T, object>> key
             return ThenByDescendingInternal(keySelector);
         }
 
-        public virtual SqlExpression<T> ThenByDescending<Table>(Expression<Func<Table, object>> keySelector)
-        {
-            return ThenByDescendingInternal(keySelector);
-        }
+        public virtual SqlExpression<T> ThenByDescending<Table>(Expression<Func<Table, object>> fields) => ThenByDescendingInternal(fields);
+        public virtual SqlExpression<T> ThenByDescending<Table1, Table2>(Expression<Func<Table1, Table2, object>> fields) => ThenByDescendingInternal(fields);
+        public virtual SqlExpression<T> ThenByDescending<Table1, Table2, Table3>(Expression<Func<Table1, Table2, Table3, object>> fields) => ThenByDescendingInternal(fields);
+        public virtual SqlExpression<T> ThenByDescending<Table1, Table2, Table3, Table4>(Expression<Func<Table1, Table2, Table3, Table4, object>> fields) => ThenByDescendingInternal(fields);
+        public virtual SqlExpression<T> ThenByDescending<Table1, Table2, Table3, Table4, Table5>(Expression<Func<Table1, Table2, Table3, Table4, Table5, object>> fields) => ThenByDescendingInternal(fields);
 
         private SqlExpression<T> ThenByDescendingInternal(Expression keySelector)
         {

tests/ServiceStack.OrmLite.Tests/OrderByTests.cs

@@ -52,6 +52,30 @@ public void Can_OrderBy_and_ThenBy()
                 Assert.That(tracks.First().Letter, Is.EqualTo("A"));
                 Assert.That(tracks.Last().Letter, Is.EqualTo("C"));
             }
-        }        
+        }
+
+        [Test]
+        public void Can_OrderBy_multi_table_expression()
+        {
+            using (var db = OpenDbConnection())
+            {
+                db.DropAndCreateTable<LetterFrequency>();
+                db.DropAndCreateTable<LetterWeighting>();
+
+                var letters = "A,B,C,D,E".Split(',');
+                var i = 0;
+                letters.Each(letter => {
+                    var id = db.Insert(new LetterFrequency {Letter = letter}, selectIdentity: true);
+                    db.Insert(new LetterWeighting {LetterFrequencyId = id, Weighting = ++i * 10});
+                });
+
+                var q = db.From<LetterFrequency>()
+                    .Join<LetterWeighting>()
+                    .OrderBy<LetterFrequency, LetterWeighting>((f, w) => f.Id > w.Weighting ? f.Id : w.Weighting);
+
+                var results = db.Select(q);
+            }
+        }
+        
     }
 }